PROPORTIONAL PRESSURE CONTROLLER WITH INLET AND EXHAUST POPPETS AND PRESSURE SIGNALLING

摘要

Disclosed is a proportional pressure controller (10). The controller includes: a body (12) having inlet (28), outlet (30), and exhaust ports (30); a fill valve (54); a dump valve (56); an inlet poppet valve (36) and an exhaust poppet valve (80); an outlet flow passage (34); a fill inlet passage (62); and a first pressure signalling device (110). The fill valve is in communication with a pressurized fluid in the inlet port, and the dump valve is in communication with the pressurized fluid in a discharge passage of the fill valve. The outlet flow passage is in communication with the pressurized fluid when the inlet poppet valve is moved to an inlet poppet valve open position. The outlet flow passage communicates with the outlet port and an exhaust/outlet common passage (88). The exhaust /outlet common passage is normally isolated from the exhaust port when the exhaust poppet valve is in an exhaust poppet valve closed position. The fill inlet passage provides fluid communication between an inlet flow passage (58) and the fill valve, and is isolated from each of the outlet flow passage, the exhaust/outlet common passage, and the outlet and exhaust ports in all operating conditions of the controller. The fill inlet passage communicates with the inlet passage and is continuously pressurized by the pressurized fluid in the inlet passage. The signalling device outputs a sensed pressure signal, and is positioned in the discharge passage downstream of the fill valve to isolate the pressure signalling device from fluid in the outlet port.